flagg



Jan. 27, 1959 R. P. FLAGG COMBINATION VALVE AND SAFETY PILOT Filed Spt.9, 1957 3 Sheets-Sheet 2 INVENTOR. RAYMOND P FLAGG AT TOR/VE Y Jan. 27,1959 .R. P. FLAGG 2,871,311

COMBINATION VALVE AND SAFETY PILOT Filed Sept. 9, 1957 5 Sheets-Sheet 3Q 37d Y INVENTOR. RAYMOND F! FLAGG /QQX ATTORNEY nite tat COMBINATIONVALVE AND SAFETY PILOT Raymond P. Flagg, Golden Valley, Minn assignor toMinneapolis-Honeywell Regulator Company, Minneapolis, Miun., acorporation of Delaware Application September 9, 1957, Serial No.682,792 Claims. (Cl. ZOO-61.86)

- inexpensive, and reliable attachment for an electrica ly operated mainor control gas valve. It can convert an electrically operated valve intoa single compact unit which provides not only control of the main gas toa furnace but also safety shutdown of the main burner as well as controlof the pilot burner, by the pilot valve embodied therein, all withoutincreasing the overall size ofthe assembly toany great extent.

One of the objects of the invention is to provide an add on safety pilotattachment for an electrically operated valve so as to not increase theoverall size of the.valve too great an amount;

Another object of the invention is to provide a very compact attachmentfor an electric valve in which a switch and a pilot valve are adapted.to-be held in closed and opened positions, respectively, by means of aflame responsive control member;

Still another object of the invention is to provide a 100% safety reset,safety pilot attachment for an electrically operated valve, wherein acombined on-olf and adjustable flow plug valve are compactly arrangedtherein, in series with the safety pilot valve.

-Still further objects of the invention will become apparent uponreading the following detailed description of the-invention inconjunction with the accompanying drawing wherein: a

Figure l is a vertical sectional view of the invention;

Figure 2 is a vertical end view of the invention, as viewed from theleft-hand end thereof in Figure 1 of the drawing and with a portionthereof broken away;

Figure 3 is a side view of the safety pilot portion of the invention;

Figure 4 is a plan view of the invention with portions thereof brokenaway;

Figure 5 is a sectional view of the switch portion of the inventiontaken along line 5-5 of Figure 1; and

Figure 6 is a sectional view taken along line 6-6 of Figure 4.

As the details of the electrically operated valve 11 form no part of theinvention, the components of the control or main valve will be onlybriefly described. It consistsof a valve body 12 having a threaded inlet13, a threaded outlet 14, and a valve seat 15 therebetween. A housing 16is secured to the body 12 and has a main gas control valve 17 pivotedthereon so as to cooperate with the valve seat 15. This valve is adaptedto be atent 0 ice actuated, through a yoke 18, by a plunger 19positioned within a solenoid coil 20. Energization of the coil windingcauses the plunger to move inwardly of the coil and rock the valvecarrying lever on its pivotal connection with the housing 16, to openthe valve 17. One end 21 of the coil is connected to a central terminal22 of a terminal block 23 while the other end 24 of the coil isconnected to the terminal 25 (Figure 4).

The terminal block 23 forms a portion of the safety pilot section of theinvention that can be added to an electrically operated valve, such asthe valve illustrated in the above mentioned .lamieson application andas illustrated in Figure 1 of the drawing. The terminal block 23 issubstituted for a conventional terminal block on the cover 16a for thehousing 16.

The terminal block comprises a lower casting 26, of Bakelite or anyother suitable material and an upper casting 27 of the same material.The two castings are held together and on the cover 16a by means ofterminals 25 and 28 at each end of the terminal block. It is to be notedthat the terminal members are electrically insulated from the cover 16aby means of rings 29 and washers 30 made of suitable electricallyinsulating mate rial.

The lower casting 26 of the terminal block 23 has a recess 31 and arecess 32 in the upper surface thereof and a bore 33 extendingvertically through an end thereof that projects beyond the end of thecover 16a. The upper casting 27 has a recess 34 in the bottom surfacethereof and a vertically extending bore 35 passing through the castingin axial alignment with the bore 33 in the lower casting. A flexiblecontact blade 36 is clamped to the lower casting at one of its ends bythe head of the terminal member 22 extending through the lower casting26 while the other end of the terminal blade extends over the bore 33.An extension 36a of the blade 36 extends into the recess 32 with a fitthat prevents 'rotation of the blade 36 about the terminal 22. The

blade 36 also has a transversely extending arm 36b that serves as onecontact of the switch controlling the energization of the coil 20. Asecond contact blade 37 has a fixed end positioned between the castings26 and 27 with a reverse-bend end portion 37a (Figure 6) thatresiliently bears against the terminal 28.to provide electricalconnection therewith. Portion 3712 has an upwardly struck button portion370 that is adapted to engage the portion 36b of contact 36 to completea circuit from the terminal 28 to the coil 20 through the contactblades.

Another metallic casting 38 is secured to the terminal block 23 by meansof a screw 39 extending through the terminal block and screw threadedinto the casting 38. The lower end of the casting 38 is secured to thevalve body 12 by means of a plate 40 secured to the casting 28 by screws41 and to the valve body by screws 42. A conical bore 43 extendsdownwardly from the top of the casting 38 and terminates in a threadedbore 44. A valve seat member 45 is screw threaded into the threaded bore44 and into sealing engagement with a shoulder formed by a smallerdiameter bore 46 extending downwardly from the bore 44 and terminatingin a still smaller diameter bore 45 which, in turn terminates in an opensided chamber 47 in the lower right-hand end and side of the casting 38.

A plug valve 48 is resiliently held in the bore 43 by means of a leafspring 49 hearing downwardly on a collar 50 clamped on the plug valve bymeans of a handle 51 staked in place on the plug valve. The plug valvehas an axial passage 53 therein communicating with a radial passage 54therein which is adapted to register with a passage 55 leading to theoutlet fitting 56. A

valve stem 57 fits snugly in the bore 45 and has a valve head 58 at itsupper end that engages the valve seat 45 to control the gas flow throughthe casting 38. The rate of flow through the casting is controlled by aneedle valve 59 threaded into the plug valve so as to vary the size ofthe opening of the bores 53 and 54. Screw 52 seals the passage $3 overthe valve '59.

Gas flow to the bore 46 is from a pilot gas inlet '78 through passage 79(Fi ure 2) to filter chamber '89 and, from these, through filter 31 andpassage 82 to bore 46.

The valve stem 57 extends through a forked end of a pivoted lever 66)and has a spring strain release connection 61 with the lever. At thevery bottom of the stem 57, there is an abutment washer 62 thereonretained by a split washer e53 fitting in an annular groove 64 in thebottom of the stem. A valve is adapted to be actuated to its openposition by the forked end of the lever 6i? moving downwardly andengaging the washer 62 to pull the valvehead 58 from the valve seat 45.As can best be seen in Figure 3 of the drawing, the lever 60 has a fixedpivot 65 extending through the plate 46, through upwardly extending cars68 of the lever 60, and into a boss 66 formed on the inner wall of thecasting 38. The lever oil also has an aperture ebb therein through whichamanually operable plunger 67 extends.

The plunger 67 has asplit ring abutment shoulder 68 thereon in anannular groove for engagement with the upper surface of the lever 60near one end thereof and on'the same side of the pivot 65 as the valvestem or plunger 57. The stem is"; extends upwardly through a bore 69 inthe top wall of the casting '38 and terminates in a head portion 67athat is located in the bore 33 of casting 26 of the terminal block. Aspring 70, extending between the upper wall of casting 38 and a splitwasher 71 located in an annular groove in the stem 67 a short distancefrom the upper wall, normally biases the stem 67 downwardly away fromthe contact blade 36. As illustrated in the drawing, the lever 60 isholding the stem of plunger 67 in its uppermost position against thebias of spring "Iii to hold the blade 36 out of engagement with blade37.

A thermocouple energizable electromagnet 72 is mounted in the casting 38by means of a thermocouple connector member 72a extending through anaperture 73 in the casting and clamped in this'position by means of anut 74 threaded onto the thermocouple connector 725:. The thermocouplemagnet unit 72 is of conventional. construction and encloses or includesan armature (not shown) that is movable into and out of engagement withan electromagnet (not shown) and so arranged that the armature will beheld by the electromagnet when the coil is energized by a thermocoupleheated by a pilot burner (not shown). As illustrated in the drawing, acompression spring 75 has the stem 76 of the armature biased downwardlyagainst the other end of the lever 6t), thus holding the stem 67 andplunger 57 in their uppermost positions. The spring 75, being muchstronger than the spring '70, will force the valve closed and thecontact 36 out of engagement with the contact 37 when ever the magnet isincapable of holding the armature against it. Since the coil 2% of thesolenoid plunger that actuate-s the main valve is controlled by'the'switch blades 36 and 3'2, it is obvious that the valve 17 can notopen as long as the contact blade So ls separated from the contact blade37. It is thus seen that the arrangement of the elements of both thevalve body and of the safety pilot attachment for the valve, asillustrated in the drawing, are all in a shut-down condition.

in order to place the control apparatus for the heating system in whichit is installed in operation, a manually operable reset button 77 may bedepressed in the bore 35 so that the lower end of the button 77 engagescontact blade 36 and moves the plunger 67 downwardly against the leverso to, thereby, lift the armature stem '76 into engagement with theelectromagnet and to simultaneously lift the valve stem 57 out ofengagement with the valve seat ed. The reset button 77 has a lateralextension 77a that extends downwardly from the portion that engages theblade 36 so as to engage the blade 37 at substantially the same timethat it engages the blade 36. As the button 77 engages the two blades inits forward movement, the plunger 67 maintains the two blades inseparated relationship so that as the valve is moved to its openposition and the armature is reset, no current can flow to the coil 20.When the electromagnet has become energized due to the fact that thepilot burner has been ignited, releasing of the reset button 77 willpermit the contact blade to lift the reset button 77, due to the biasplaced thereon in the inward movement of the reset button, and to causethe contact 370 to lift up into engagement with the portion Sub on thecontact blade 35, the contact blade 36 being in its normal unflexedposition due to the fact that the plunger 67 is lowered under thecompression of spring 70. It is thus seen that only if the armature isenergized so as to hold the spring depressed, is it'possible for theswitches blades 36 and 37 to complete a circuit to the solenoid 20. Thecircuit to the main valve coil 20 is completed through a lead wire (notshown) from the terminal 65, through a room thermostat (not shown) andthrough a lead wire (not shown) from the thermostat back through a powersource to the terminal 28.

The main valve will thus be opened only if the room thermostat iscalling for heat and only as long as there is a flame present at thepilot burnerkeeping the thermocouple heated to the extent necessary toenergize the electromagnet of the unit 72.

With the main burner in operation, should there be a pilot flamefailure, the electromagnet will become tie-energized causing the spring75 to close the pilot valve and to break the contact between the blades36 and 37 and thereby close the main valve. This causes safety shutdownof all gas being supplied to the heating installation.

While I have illustrated the preferred embodiment of the invention, itis deemed to be obvious to those skilled in the art that modificationsmay be made therein without departing from the spirit of the invention.Therefore, the scope of the invention is to be determined fiom theappended claims.

I claim for my invention: 7

1. A combination main valve and pilot valve and switch comprising a mainvalve, a pilot valve, a first plunger for actuating said pilot valve, apivoted lever operably engaging said plunger, means biasing said plungerin a direction to open said pilot valve, stronger means for biasing saidlever in a direction to close said pilot valve, condition responsivemeans capable of holding said lever in but incapable of moving it tovalve open position, a pair of contact blades each having a fixed endand a free end which normallyengages the free end of theother'blade,asecond plunger normally flexing a first of said blades out ofengagement with the second blade, and manually operable means movableinto engagement with both of said blades to simultaneously move the.free ends thereof and the .two plungers to open said pilot valve Whileholding said free ends separated, said manually operable means beingmovable to its inoperative position and said second blade being movableinto contact with said first blade under the bias of the second bladeupon release of said manual means when the condition responsive means isenergized.

2. In'combination with an electrically operated control valve, a switchand pilot valve adaptor for the control valve comprising a pilot valvehousing having an inlet and an outlet with a valve seat therebetween, apilot valve cooperable with said seat, a first plunger for actuatingsaid pilot valve, a pivoted lever operably engaging said plunger, meansbiasing said plunger in a direction to open said valve, stronger meansfor biasing said lever'in a di section to close said valve, Iconditionresponsive means capable of holding said lever in but incapable ofmoving it to valve open position, a pair of contact blades each having afixed end and a free end which normally engages the free end of theother blade, a second plunger normally flexing a first of said bladesout of engagement with the second blade, manually operable means movableinto engagement with both of said blades to simultaneously move the freeends thereof and the two plungers to open said pilot valve while holdingsaid free ends separated, said manually operable means being movable toits inoperative position and said second blade being movable intocontact with said first blade under the bias of the second of saidblades upon release of said manual means when the condition responsivemeans is energized, and a terminal block partially overlying and securedto said pilot valve housing and partially overlying said control valveand being securable thereto to hold both valves in assembledrelationship.

3. A combination switch and pilot valve adaptor for an electricallyoperated main valve comprising a pilot valve housing having an inlet andan outlet with a valve seat tnerebetween, a pilot valve cooperable withsaid seat, a first plunger for actuating said pilot valve, a pivotedlever operably engaging said plunger, means biasing said plunger in adirection to open said valve, stronger means for biasing said lever in adirection to close said valve, condition responsive means capable ofholding said lever in but incapable of moving it to valve open position,a pair of contact blades each having a fixed end and a free end whichnormally engages the free end of the other blade, a second plungernormally flexing a first of said blades out of engagement with thesecond blade, and manually operable means movable into engagement withboth of said blades to simultaneously move the free ends there of andthe two plunger s to open said pilot valve while holding said free endsseparated, said manually operable means being movable to its inoperativeposition and said second blade being movable into contact with saidfirst blade under the bias of the second of said blades upon release ofsaid manual means when the condition responsive means is energized.

4. A combination switch and pilot valve adaptor for an electricallyoperated main valve comprising a pilot valve housing having an inlet andan outlet with a valve seat therebetween, a pilot valve cooperable withsaid seat, a first plunger for actuating said pilot valve, a flowadjusting valve concentric with said valve seat and plunger, a

L? pivoted lever operably engaging said plunger, means biasing saidplunger in a direction to open said valve, stronger means for biasingsaid lever in a direction to close said valve, condition responsivemeans capable of holding said lever in but incapable of moving it tovalve open position, a pair of contact blades each having a fixed endand a free end which normally engages the free end of the other blade, asecond plunger normally flexing a first of said blades out of engagementwith the second blade, and manually operable means movable intoengagement with both of said blades to simultaneously move the free endsthereof and the two plungers to open said pilot valve while holding saidfree ends separated, said manually operable means being movable to itsinoperative position and said second blade being movable into contactwith said first blade under the bias of the second of said blades uponrelease of said manual means when the condition responsive means isenergized.

5. A combination switch and pilot valve adaptor for an electricallyoperated main valve comprising a pilot valve housing having an inlet andan outlet with a valve seat therebetween, a pilot valve cooperable withsaid seat, a first plunger for actuating said valve, a pivoted leveroperably engaging said plunger, means biasing said plunger in adirection to open said valve, stronger means for biasing said lever in adirection to close said valve, condition responsive means capable ofholding said lever in but incapable of moving it to valve open position,a pair of contact blades each having a fixed end and a free end whichnormally engages the free end of the other blade, a second plungersubstantially parallel to said first plunger and normally flexing afirst of said blades out of engagement with the second blade, manuallyoperable means movable into engagement with both of said blades tosimultaneously move the free ends thereof and the two plungers to opensaid pilot valve while holding said free ends separated, said manuallyoperable means being movable to its inoperative position and said secondblade being movable into contact with said first blade under the bias ofthe second of said blades upon release of said manual means when thecondition responsive means is energized, and on a terminal blockoverlying and secured to said adaptor and having a portion thereofextending beyond said adaptor to overlie and to secure said adaptor toan electrically operated valve.

No references cited.

